Photos rejected due to technical issues. Ideas?

Technical issues are the reason given. Moderators do not have the time to point out the problems more extensively.

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The first picture exposes some technical problems: noise, overexposure and artefacts. In addition the colours are washed out due to the aggressive in camera post processing.

The second picture is quite the same. In addition you would need model releases from the musicians and probably a property release from the concert venue. Generally it is only allowed to take pictures from concerts with small cameras (like your phone camera) because they do not provide enough quality for professional pictures. Musicians want to control their image and generally have a very restrictive protocoll for concert photographers.